In the automotive vehicle manufacturing industry, it is customary to install various parts onto a fixture or an end effector frame of a robotic manipulator to produce a vehicle sub assembly or full body capsule assembly. The vehicle assembly process starts with sub assembly fixtures or tooling cells that require location features to address geometric control of the vehicle build. In this sub assembly scenario and similar applications, a multi-tool positioner unit can be used to support multiple tooling arrangements to allow more than one type of vehicle sub assembly to be processed through the fixture or tooling cell, thereby making the fixture or tooling cell flexible. Likewise, mainline assembly tooling can also be made flexible by using multi-tool positioner units. For techniques of marrying an automotive body parts, see U.S. patent application Ser. Nos. 11/112,599 and 60/632,117, which are assigned to the assignee of this application and incorporated by reference herein in their entirety.
Multi-tool positioners are used to set geometry or to assist in securing automotive body parts so that the general operating process can be performed to create a part assembly that meets specifications. Typically as many as about twelve multi-tool positioner units may be used in a fixture and pallet tooling, depending on the parts being assembled. In use, an operator (or automatic equipment) loads an automotive component part, for example, a wheel house inner or even an entire underbody assembly, onto the pallet/fixture. The multi-tool positioner units hold the component parts in position. In the event that a different specified part is entered in to the system the multi-tool positioner units can be manipulated to the required location to accommodate the entering part.
The multi-tool positioner unit must be able to be moved in three orthogonal directions to achieve the required flexibility. The unit is adjustable through a braking system. The braking system may be released to reconfigure the multi-tool positioner unit to a different required position. More particularly, the multi-tool positioner units can be repositioned by engaging socket type connections, either manually or by using robotic end of arm tooling. From any given position, the brakes may be released individually or sequentially to obtain the next desired position. Once the next position is obtained, the manual device or robotic end of arm tooling will engage the brake to hold the multi-tool positioner unit in that position. The multi-tool positioner units must also accommodate locational tolerances required to compensate for manufacturing tolerances inherent in the various body parts and in the multi-tool positioner unit itself, while holding the tool in the desired position. Moreover, the brakes should be able to withstand minor collisions or pressure exerted by external forces.
Conventional multi-tool positioner units generally include spherical bearings in the lower pivot assembly to provide positional compliance and/or locational tolerance. Upper pivot assemblies hold a desired position with surface contact bearing method utilizing coated fitted bearings.